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Discussion Starter · #1 ·
Hi All

So I have been on MX5NUTZ for quite some time, but not got around to posting anything. Now maybe a good time as I am about to embark on my first engine build adventure.

Okay so I have a 1998 1.8 NB Japanese import, which I bought off a very good friend of mine at the beginning of 2017. The car was his show car, for his JDM custom business and had been prepared extremely well for a good track car. The car is running a Garrat T25 AR42 turbo, at 6psi. You may ask why only 6psi and not more boost, well to be honest the car has not let me down on many days of hard driving therefore up to now I have been happy with how it is. The only major thing, I have had to do is change a seized oil pump, for a forged boundary pump.

I now feel it is time for more power, well too be honest more acceleration out of corners and straight line speed. So now the plan is to go for more boost..........

I have just taken delivery of a second hand engine, which is my winter project. The plan is to strip it first and then decide the next steps. This will be an ever evolving project, learning on the way and certainly do things correct and not cutting corners. Speaking with James today at Bofiracing, he has given me some good pointers to start with, so let's see where this all ends up. Hopefully not a big bang and lots of smoke.
 

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Discussion Starter · #3 ·
I thought I would put a couple of pictures up, if anyone was interested. The one with the engine support beam, was when I changed the oil pump....Check my secondhand engine today, looks like it is a VVT rather than standard as is in my car. Looks like a bit of reading and googling tonight is required
 

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Discussion Starter · #4 ·
Managed to get the engine through the house yesterday, with little drama. Most importantly before my wife arrived home. It is now stripped down and ready to be cleaned.
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Discussion Starter · #5 ·
Really enjoyed breaking the engine down, first time for everything. Hope I have taken enough pictures and labelled everything correctly. I have just removed the head and left as it is. Everything is off the block, apart for the internals.
 

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Discussion Starter · #7 ·
Hi Rich

This seems to be an ever evolving process, with the end goal to gain more speed and power on track. I could go for just new rods, bearings and a crank balance with a standalone ECU, probably a Motorsport ME442. This should be good for 300bhp, from what I understand, but it does not give me any flexibility to increase power at a later stage. So I will also change the pistons for forged ones. Everything else in the car, is currently setup to allow these upgrades.
Looking at the crank last night, looks like there is quite a lot of wear on it, so that's my next job to understand why.
 

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layabout
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Looking at the crank last night, looks like there is quite a lot of wear on it, so that's my next job to understand why.
whats it look like? measured or just visable?

1.8 engines are evrywhere & cheap, if the crank is damaged I'd look for a replacement (y)

Rich.
 

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Discussion Starter · #9 ·
whats it look like? measured or just visable?

1.8 engines are evrywhere & cheap, if the crank is damaged I'd look for a replacement (y)

Rich.
Looking at the crank a bit closer it actually looks okay, I will start measuring after the weekend and see how it measures up
 

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Discussion Starter · #10 ·
I am really enjoying this project, hope I can say the same when it’s all finished. I have been cleaning the block, ready for painting. It was quite rusty so, I used my drill with rotary wire brushes, and it is coming up quite well. Needs a bit more work, then it will be ready to go to the machine shop. I was thinking of painting it first, but I will have the bores done first then paint.
Speaking of the bores, I have checked the diameter and they all measure up in spec at 83mm….Now I need to plan whether to go 84mm or 84.5mm.
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I measured the journals on the crank also and they are all in spec, which is good news.
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More reading and YouTube tonight to make the next decisions, and I will speak with Bofiracing again tomorrow.
 

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Discussion Starter · #12 ·
Looks like you're getting good and stuck in.
Hopefully you already know this, but there's some loom and sensor changes that you'll need to do. And depending on what ECU you use, you might need to change your ECU if it doesn't have VVT control.
Yes very much so getting stuck in and enjoying it also.
Thank you for your advice. I have read about the Loom and sensors changes, there seems to be conflicting opinions. I know I have to re route the wiring for the Cam sensor and change the ECU. My plan is to fit a ME442 ECU and re-wire the cam sensor, but before I buy any internals need to check if there are any further mods - Lots to learn I know.
 

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layabout
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as you've got the bare cylinderblock I'd advise removint the 2 brass oil-gallery plugs (front & rear face of block) and the cyiliderhead's oilfeed / one-way valve (top of cylinderblock, seen in your ohoto between cylinder 2&3, lower edge)



this means you can actually clean all the swarf & muck from the oilway drillings prior to assembly (y)

NEVER believe something is clean........

I posted removal of brass oilway plugs




from 50 Shades Of Silver (Na Eunos)

Rich.
 

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Discussion Starter · #14 ·
as you've got the bare cylinderblock I'd advise removint the 2 brass oil-gallery plugs (front & rear face of block) and the cyiliderhead's oilfeed / one-way valve (top of cylinderblock, seen in your ohoto between cylinder 2&3, lower edge)



this means you can actually clean all the swarf & muck from the oilway drillings prior to assembly (y)

NEVER believe something is clean........

I posted removal of brass oilway plugs




from 50 Shades Of Silver (Na Eunos)

Rich.
Hi Rich
Thank you for the heads up, I have just checked your write up on removing the plugs, I was wondering how I would remove them
 

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Discussion Starter · #16 ·
Yes very much so getting stuck in and enjoying it also.
Thank you for your advice. I have read about the Loom and sensors changes, there seems to be conflicting opinions. I know I have to re route the wiring for the Cam sensor and change the ECU. My plan is to fit a ME442 ECU and re-wire the cam sensor, but before I buy any internals need to check if there are any further mods - Lots to learn I know.
I have just spoken with Bofiracing and they have mentioned that I can use the NB1 head from my original engine and use it on the NB2 block - I need to checked this out, but this seems like the simplest option.
 

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Discussion Starter · #18 ·
Where do I start apart from I should listen to advise and read more. So I started to remove the plugs from the engine, quite simple until one of them got stuck against the side of the bore. I thought I would drill a hole in the plug so I could lever the plug out. Only problem was when the drill popped through the plug, it continued to drill into the bore side. Argh I now have a small hole in the side of the bore, not all the way through but about 2mm to 3mm deep. I should of listened to what Zed had mentioned, and drilled the plugs first.
Now I am not sure if I have made the wall of the bore weak, because of the small indent in the side.....I think I have three options 1) Take the block to a machine shop, to check if they recommend boring the pistons. 2) Buy another block and do the work again, this time properly 3) Drop my engine out of the car and work on this one, I have two more trackdays this year so I cannot start this until mid December.....More decisions to make other the weekend, but I think I will try option one first
 
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